Improvement in making slagware



UNITED STATES PATENT OFFICE.

XVILLIAM G. ELLIOTT, OF BLISWORTH, ENGLAND.

lMF ROVEMENT IN MAKING' SLAGWARE.

Specification forming part of Letters Patent No. l I.692, datedSeptember 19, 1854.

To all whom it may concern:

Be it known that I, WILLIAM GILBERT EL.- LIOTT,0fBliSWOltlJ,iI1thBcounty ofNorthampton, gentleman, a subject of the Queen of GreatBritaimhave invented or discovered a new and useful improvement in themanufacture of bricks, tiles, pipes, and other articles capable of beingmolded and I,the said WILLIAM GILBERT ELLIOTT, do hereby declare thenature of the said invention and the manner in which the same is to beperformed are fully described and ascertained in and by the followinginstrument in writing-that is to say:

My invention consists in an improvement in manufacturing bricks, pipes,tiles, and other articles from the slag of the smelting or blastfurnaces of iron-works, or from an artificial slag of a like natureproduced by fusing together chalk, clay, limestone, or some of thefluxes.

The slag from the blast or smelting furnaces of the iron-works hasusually been suffered to run to waste, and its disposal is often asource of much expense to the proprietors of such works. Although theiron slag has occasionally been run or molded in lumps, blocks, ormasses direct from the furnaces, and has been employed in building roughwalls, the slag ot' the iron-works has usually been regarded as refusematter, and a great encumbrance to the land in the vicinity of theworks. Now, I have discovered that such iron slag, and also theartificial slag above mentioned, may becon verted into profitable anduseful commodities as follows: As the slag from the ironfurnaces isusually run to waste in the open air, 1 provide, as close as convenientto the furnace from which the slag runs, in an inclosed building, moldsof metal or other proper materials of the forms or shapes suitable forthe production of such articles as it may be desired to make of theslag, and I catch the slag in the open air in a large covered ladle orother vessel, which, when full, I convey into the inclosed building, andthen run the slag, in a melted or fused state, into such molds. When asufficient quantity has been sufiered to run into the molds, accordingto the size or form of the article to be manufactured, and in order tofinish the article in the desired form, I subject the molten material toheavy pressure in the mold, and while it is therein, and before itbecomescompacted, I pierce it in various directions by means of rods,which, if necessary, may be made hollow to contain water, so that theymay not be destroyed by the great heat of the material. In some-casesthese rods or piecers may be applied directly to the stamper, and in allthey are intended to aid in the expulsion of the gases from the moltenslag, thepiercingof it by them serving to open it and allow of theescape from it of the gases, so that the compression of the slag may bemore perfectly et fected than would be the case were the gases sufferedto remain in it. By such means the desired form is given toeach casting,and more uniform thickness, density, and coherence to the product, andconsequently less contraction is caused in cooling than if the mold wasfirst filled and the gases were allowed to remain or to escape by thecontraction in cooling without receiving such pressureand piercing. Themolded or cast articles are nextto be removed from the molds, andgradually cooled or annealed in an oven or furnace, so as to be freefrom the brittleness which would otherwise render the articlescomparatively useless. The gases in the slag as it is produced from afurnace cause it to have aspon gy appearance, and render it of little orno value. They must be driven out of it before its particles can besufficiently compacted together. This expulsion of the gases is anessential feature of my invention by means of piercing and pressure.

I am aware that in molding glass or metal pressure has been employed inorder to force the molten metal into the crevices of the mold, butneither the pressure or piercing has ever been used in'relation to or onslag as I use it in the manufacture of thick heavy substances ormasses-that is, to the extent suflicient to expel the injurious gasesfrom the slag or a material of like nature when in a liquid or fluidstate in the mold. It is therefore a new feature in making articles ofmolten slagto expel its gases by piercing and pressure at the same time,and to subsequently anneal the compound slag, which, without the latterprocess, would be of little or no value, as it would be certain to crackor break if too suddenly cooled, or even subjected to beingcoolcd,byexposurein an ordinary atmosphere.

Instead of producing rough, heavy, irregular, or brittle masses, such ashave heretofore been. occasionally made, the slag by my process isconverted into bricks, pipes,"tiles, and other articles fit for thepurposes to which such well-finished articles are commonly employed.

The manufacture hereinbefore described is from the slag in a fluid stateas it leaves the blast or smelting furnaces of the iron-works; but asthe manufacture becomes general cases may occur in which it may becommercially profitable to construct furnaces for the express purpose ofremelting the refuse slag, or of 0btaining from the raw or naturalmaterials in any particular locality the liquid mass analogous to slagand employing it in and for the manufacture of bricks, pipes, tiles, andother articles, as before described.

And now, having described the nature of my said invention and in whatmanner the same is to be performed, I declare that I do not claim as ofmy invention piercing-rods, presses, Stampers, rollers, and molds forhollow and pierced bricks, pipes, or other artiolesof any other shape orform; nor annealing ovens nor furnaces; but

I claim as my invention- The improvement in the manufacture of bricks,pipes, tiles, and other articles capable of being molded from slag (orfrom a liquid mass analogous to slag) in a melted or fused state, suchimprovement consisting in expellingthe gases of theslag by piercing andpressure at the same time when the slag is in a mold.

In witness whereof I, the said WILLIAM GIL- BERT ELLIOTT, have hereuntoset my hand and seal this16th day of February, in the year of our Lord1854.

WM. G. ELLIOTT. ['L. s.]

\Vitnesses:

GEO. PITT,

4 Old Square. WILLIAM EWING, N 0. 4 Prince Street Ban-7r.

